1. Field of the Invention
This invention relates to devices for illuminating a subject to be photographed by a camera having a zoom lens.
2. Description Relative to the Prior Art
It is axiomatic that as a zoom camera is zoomed from wide angle to telephoto, so the field of view decreases. Likewise the field of view increases as the camera is zoomed from telephoto to wide angle. If the source of flash illumination associated with the camera, be it a separate gun or a built in strobe, is constructed so that it properly illuminates the scene for a wide angle photograph, then much of the light from the source will be wasted when a telephoto photograph is taken. Similarly, if the source is constructed so that it properly illuminates the scene for a telephoto photograph, then much of the scene will be underlit when the camera is set for a wide angle photograph.
Proposals have been made for overcoming the above-described problem. Such proposals have included a fresnel lens movable between positions in which it is in, and in which it is out of, the light path from the source, in order to vary the included angle of the light beam. Another proposal has included moving the flash tube relative to the reflector so that the included angle of the projected beam is changed. Both proposals have been found to be liable to create uneven illumination of the subject being photographed. It is believed that such uneven illumination is created by shadows of the flash tube.